{"id":48243,"date":"2019-11-08T19:19:35","date_gmt":"2019-11-08T18:19:35","guid":{"rendered":"https:\/\/www.thermal-engineering.org\/o-que-e-processo-isentropico-definicao\/"},"modified":"2020-01-28T13:56:59","modified_gmt":"2020-01-28T12:56:59","slug":"o-que-e-processo-isentropico-definicao","status":"publish","type":"post","link":"https:\/\/www.thermal-engineering.org\/pt-br\/o-que-e-processo-isentropico-definicao\/","title":{"rendered":"O que \u00e9 processo isentr\u00f3pico &#8211; defini\u00e7\u00e3o"},"content":{"rendered":"<div class=\"su-quote su-quote-style-default\">\n<div class=\"su-quote-inner su-clearfix\">Um processo isentr\u00f3pico \u00e9 um processo termodin\u00e2mico, no qual a entropia do fluido ou g\u00e1s permanece constante. \u00c9 tamb\u00e9m chamado de processo de entropia constante. Engenharia T\u00e9rmica<\/div>\n<\/div>\n<div><\/div>\n<div>\n<div class=\"lgc-column lgc-grid-parent lgc-grid-50 lgc-tablet-grid-50 lgc-mobile-grid-100 lgc-equal-heights  lgc-first\">\n<div class=\"inside-grid-column\">\n<h2><span>Processo isentr\u00f3pico<\/span><\/h2>\n<p><span>Um\u00a0<\/span><strong><span>processo isentr\u00f3pico<\/span><\/strong><span>\u00a0\u00e9 um\u00a0<\/span><a title=\"Processos termodin\u00e2micos\" href=\"https:\/\/www.thermal-engineering.org\/pt-br\/o-que-e-processo-termodinamico-definicao\/\"><strong><span>processo termodin\u00e2mico<\/span><\/strong><\/a><span>\u00a0, no qual a\u00a0<\/span><a title=\"O que \u00e9 entropia\" href=\"https:\/\/www.nuclear-power.com\/nuclear-engineering\/thermodynamics\/what-is-energy-physics\/what-is-entropy\/\"><strong><span>entropia<\/span><\/strong>\u00a0<\/a><span>do fluido ou g\u00e1s permanece constante.\u00a0Isso significa que o\u00a0<\/span><strong><span>processo isentr\u00f3pico<\/span><\/strong><span>\u00a0\u00e9 um caso especial de um\u00a0<\/span><strong><span>processo adiab\u00e1tico<\/span><\/strong><span>\u00a0no qual n\u00e3o h\u00e1 transfer\u00eancia de calor ou mat\u00e9ria.\u00a0\u00c9 um\u00a0<\/span><strong><span>processo adiab\u00e1tico revers\u00edvel<\/span><\/strong><span>\u00a0.\u00a0Um\u00a0<\/span><strong><span>processo isentr\u00f3pico<\/span><\/strong><span>\u00a0tamb\u00e9m pode ser chamado de processo de entropia constante.\u00a0Na engenharia, esse processo idealizado \u00e9 muito \u00fatil para compara\u00e7\u00e3o com processos reais.<\/span><\/p>\n<p><span>Como existem mudan\u00e7as na\u00a0<\/span><a href=\"https:\/\/www.thermal-engineering.org\/pt-br\/o-que-e-energia-interna-energia-termica-definicao\/\"><span>energia interna<\/span><\/a><span>\u00a0(dU) e no volume do sistema (\u2206V), os engenheiros costumam usar a\u00a0<\/span><a title=\"O que \u00e9 entalpia\" href=\"https:\/\/www.nuclear-power.com\/nuclear-engineering\/thermodynamics\/what-is-energy-physics\/what-is-enthalpy\/\"><strong><span>entalpia<\/span><\/strong><\/a><span>\u00a0do sistema, que \u00e9 definida como:<\/span><\/p>\n<p><strong><em><span>H = U + pV<\/span><\/em><\/strong><\/p>\n<p><span>Em muitas an\u00e1lises termodin\u00e2micas, \u00e9 conveniente usar a\u00a0<\/span><strong><span>entalpia em<\/span><\/strong><span>\u00a0vez da energia interna.\u00a0Especialmente no caso da\u00a0<\/span><strong><span>primeira lei da termodin\u00e2mica<\/span><\/strong><span>\u00a0.<\/span><\/p>\n<div class=\"su-spacer\"><\/div>\n<div class=\"su-spacer\"><\/div>\n<h2><span>Processo isentr\u00f3pico e a primeira lei<\/span><\/h2>\n<p><span>A\u00a0<\/span><strong><a title=\"Primeira lei em termos de entalpia dH = dQ + Vdp\" href=\"https:\/\/www.nuclear-power.com\/nuclear-engineering\/thermodynamics\/laws-of-thermodynamics\/first-law-of-thermodynamics\/first-law-in-terms-of-enthalpy-dh-dq-vdp\/\"><span>primeira lei da termodin\u00e2mica em termos de entalpia<\/span><\/a><\/strong><span>\u00a0:<\/span><\/p>\n<p><strong><span>dH = dQ + Vdp<\/span><\/strong><\/p>\n<p><strong><span>ou<\/span><\/strong><\/p>\n<p><strong><span>dH = TdS + Vdp<\/span><\/strong><\/p>\n<\/div>\n<\/div>\n<div class=\"lgc-column lgc-grid-parent lgc-grid-50 lgc-tablet-grid-50 lgc-mobile-grid-100 lgc-equal-heights  lgc-last\">\n<div class=\"inside-grid-column\">\n<figure id=\"attachment_17280\" class=\"wp-caption aligncenter\" aria-describedby=\"caption-attachment-17280\"><a href=\"https:\/\/thermal-engineering.org\/wp-content\/uploads\/2019\/05\/Isentropic-Process-characteristics.png\"><img loading=\"lazy\" class=\"size-full wp-image-17280 lazy-loaded\" src=\"https:\/\/thermal-engineering.org\/wp-content\/uploads\/2019\/05\/Isentropic-Process-characteristics.png\" alt=\"Processo isentr\u00f3pico - caracter\u00edsticas\" width=\"386\" height=\"609\" data-lazy-type=\"image\" data-src=\"https:\/\/thermal-engineering.org\/wp-content\/uploads\/2019\/05\/Isentropic-Process-characteristics.png\" \/><\/a><figcaption id=\"caption-attachment-17280\" class=\"wp-caption-text\"><span>Tabela de caracter\u00edsticas principais<\/span><\/figcaption><\/figure>\n<p><span>Veja tamb\u00e9m:\u00a0<\/span><a title=\"Primeira Lei da Termodin\u00e2mica\" href=\"https:\/\/www.thermal-engineering.org\/pt-br\/o-que-e-a-primeira-lei-da-termodinamica-definicao\/\"><span>Primeira lei da termodin\u00e2mica<\/span><\/a><\/p>\n<p><span>Veja tamb\u00e9m:\u00a0<\/span><a title=\"Lei do g\u00e1s ideal\" href=\"https:\/\/www.nuclear-power.com\/nuclear-engineering\/thermodynamics\/ideal-gas-law\/\"><span>Lei do g\u00e1s ideal<\/span><\/a><\/p>\n<p><span>Veja tamb\u00e9m:\u00a0<\/span><a title=\"O que \u00e9 entalpia\" href=\"https:\/\/www.nuclear-power.com\/nuclear-engineering\/thermodynamics\/what-is-energy-physics\/what-is-enthalpy\/\"><span>O que \u00e9 entalpia<\/span><\/a><\/p>\n<\/div>\n<\/div>\n<div class=\"lgc-column lgc-grid-parent lgc-grid-100 lgc-tablet-grid-100 lgc-mobile-grid-100 lgc-equal-heights  lgc-first lgc-last\">\n<div class=\"inside-grid-column\"><span>Nesta equa\u00e7\u00e3o, o termo\u00a0<\/span><strong><span>Vdp<\/span><\/strong><span>\u00a0\u00e9 um\u00a0<\/span><strong><span>trabalho de processo de fluxo.\u00a0<\/span><\/strong><span>Este trabalho, Vdp, \u00e9 usado para sistemas de fluxo aberto, como uma turbina ou uma bomba na qual existe um &#8220;dp&#8221;, ou seja, mudan\u00e7a de press\u00e3o.\u00a0Como pode ser visto, essa forma de lei\u00a0<\/span><strong><span>simplifica a descri\u00e7\u00e3o da transfer\u00eancia de energia<\/span><\/strong><span>\u00a0.\u00a0<\/span><strong><span>Na entropia constante<\/span><\/strong><span>\u00a0, ou seja, no processo isentr\u00f3pico, a\u00a0<\/span><strong><span>mudan\u00e7a de entalpia<\/span><\/strong><span>\u00a0\u00e9 igual ao\u00a0<\/span><strong><span>trabalho do processo de fluxo<\/span><\/strong><span>\u00a0realizado no ou pelo sistema:<\/span><strong><span>Processo isentr\u00f3pico (dQ = 0):<\/span><\/strong><\/p>\n<p><strong><span>dH = Vdp \u2192 W = H\u00a0<\/span><\/strong><strong><sub><span>2<\/span><\/sub><\/strong><strong><span>\u00a0&#8211; H\u00a0<\/span><\/strong><strong><sub><span>1<\/span><\/sub><\/strong><strong><span>\u00a0\u00a0\u00a0\u00a0\u00a0\u2192 H\u00a0<\/span><\/strong><strong><sub><span>2<\/span><\/sub><\/strong><strong><span>\u00a0&#8211; H\u00a0<\/span><\/strong><strong><sub><span>1<\/span><\/sub><\/strong><strong><span>\u00a0=\u00a0<\/span><em><span>C\u00a0<\/span><\/em><\/strong><strong><em><sub><span>P<\/span><\/sub><\/em><\/strong><strong><em><span>\u00a0(T\u00a0<\/span><\/em><\/strong><strong><em><sub><span>2<\/span><\/sub><\/em><\/strong><strong><em><span>\u00a0&#8211; T\u00a0<\/span><\/em><\/strong><strong><em><sub><span>1<\/span><\/sub><\/em><\/strong><strong><em><span>\u00a0) \u00a0\u00a0\u00a0<\/span><\/em><\/strong><em><span>\u00a0(para\u00a0<\/span><a title=\"O que \u00e9 o g\u00e1s ideal\" href=\"https:\/\/www.nuclear-power.com\/nuclear-engineering\/thermodynamics\/ideal-gas-law\/what-is-ideal-gas\/\"><span>g\u00e1s ideal<\/span><\/a><span>\u00a0)<\/span><\/em><\/p>\n<\/div>\n<\/div>\n<div class=\"lgc-column lgc-grid-parent lgc-grid-100 lgc-tablet-grid-100 lgc-mobile-grid-100 lgc-equal-heights  lgc-first lgc-last\">\n<div class=\"inside-grid-column\">\n<div class=\"su-spacer\"><\/div>\n<h2><span>Expans\u00e3o Isentr\u00f3pica &#8211; Compress\u00e3o Isentr\u00f3pica<\/span><\/h2>\n<p><span>Veja tamb\u00e9m:\u00a0<\/span><a title=\"O que \u00e9 o g\u00e1s ideal\" href=\"https:\/\/www.nuclear-power.com\/nuclear-engineering\/thermodynamics\/ideal-gas-law\/what-is-ideal-gas\/\"><span>O que \u00e9 um g\u00e1s ideal<\/span><\/a><\/p>\n<p><span>Num\u00a0<\/span><a title=\"O que \u00e9 o g\u00e1s ideal\" href=\"https:\/\/www.nuclear-power.com\/nuclear-engineering\/thermodynamics\/ideal-gas-law\/what-is-ideal-gas\/\"><span>g\u00e1s ideal<\/span><\/a><span>\u00a0, as mol\u00e9culas n\u00e3o t\u00eam volume e n\u00e3o interagem.\u00a0De acordo com a\u00a0<\/span><a title=\"Lei do g\u00e1s ideal\" href=\"https:\/\/www.nuclear-power.com\/nuclear-engineering\/thermodynamics\/ideal-gas-law\/\"><span>lei ideal dos gases<\/span><\/a><span>\u00a0, a\u00a0<\/span><a title=\"O que \u00e9 press\u00e3o - F\u00edsica\" href=\"https:\/\/www.nuclear-power.com\/nuclear-engineering\/thermodynamics\/thermodynamic-properties\/what-is-pressure-physics\/\"><span>press\u00e3o<\/span><\/a><span>\u00a0varia linearmente com a\u00a0<\/span><a title=\"O que \u00e9 temperatura - F\u00edsica\" href=\"https:\/\/www.thermal-engineering.org\/pt-br\/o-que-e-temperatura-fisica-definicao\/\"><span>temperatura<\/span><\/a><span>\u00a0e a quantidade e inversamente com o\u00a0<\/span><a title=\"O que \u00e9 volume - F\u00edsica\" href=\"https:\/\/www.nuclear-power.com\/nuclear-engineering\/thermodynamics\/thermodynamic-properties\/what-is-volume-physics\/\"><span>volume<\/span><\/a><span>\u00a0.<\/span><\/p>\n<p><strong><em><span>pV = nRT<\/span><\/em><\/strong><\/p>\n<p><span>Onde:<\/span><\/p>\n<ul>\n<li><em><span>p<\/span><\/em><span>\u00a0\u00e9 a press\u00e3o absoluta do g\u00e1s<\/span><\/li>\n<li><em><span>n<\/span><\/em><span>\u00a0\u00e9 a quantidade de subst\u00e2ncia<\/span><\/li>\n<li><em><span>T<\/span><\/em><span>\u00a0\u00e9 a temperatura absoluta<\/span><\/li>\n<li><em><span>V<\/span><\/em><span>\u00a0\u00e9 o volume<\/span><\/li>\n<li><em><span>R<\/span><\/em><span>\u00a0\u00a0\u00e9 a constante de g\u00e1s ideal, ou universal, igual ao produto da constante de Boltzmann e da constante de Avogadro,<\/span><\/li>\n<\/ul>\n<p><span>Nesta equa\u00e7\u00e3o, o s\u00edmbolo R \u00e9 uma constante chamada constante\u00a0<\/span><strong><span>universal de g\u00e1s<\/span><\/strong><span>\u00a0que tem o mesmo valor para todos os gases &#8211; ou seja, R = 8,31 J \/ mol K.<\/span><\/p>\n<p><span>O\u00a0<\/span><strong><span>processo isentr\u00f3pico<\/span><\/strong><span>\u00a0(um caso especial de processo adiab\u00e1tico) pode ser expresso com a\u00a0<\/span><strong><span>lei dos gases ideais<\/span><\/strong><span>\u00a0como:<\/span><\/p>\n<p><strong><em><span>pV\u00a0<\/span><sup><span>\u03ba<\/span><\/sup><span>\u00a0= constante<\/span><\/em><\/strong><\/p>\n<p><span>ou<\/span><\/p>\n<p><em><strong><span>p\u00a0<\/span><sub><span>1<\/span><\/sub><span>\u00a0V\u00a0<\/span><sub><span>1\u00a0<\/span><\/sub><sup><span>k<\/span><\/sup><span>\u00a0= p\u00a0<\/span><sub><span>2<\/span><\/sub><span>\u00a0V\u00a0<\/span><sub><span>2\u00a0<\/span><\/sub><sup><span>k<\/span><\/sup><\/strong><\/em><\/p>\n<p><span>em que\u00a0<\/span><strong><span>\u03ba = c\u00a0<\/span><sub><span>p<\/span><\/sub><span>\u00a0\/ c\u00a0<\/span><sub><span>v<\/span><\/sub><\/strong><span>\u00a0\u00e9 a propor\u00e7\u00e3o de\u00a0<a title=\"Capacidade t\u00e9rmica - Capacidade t\u00e9rmica espec\u00edfica\" href=\"https:\/\/www.nuclear-power.com\/nuclear-engineering\/thermodynamics\/laws-of-thermodynamics\/first-law-of-thermodynamics\/heat-capacity\/\"><strong>aquecimentos espec\u00edficos<\/strong><\/a>\u00a0(ou\u00a0<strong>capacidades de calor<\/strong>\u00a0) para o g\u00e1s.\u00a0Um para\u00a0<strong>press\u00e3o constante (c\u00a0<\/strong><strong><sub>p<\/sub><\/strong><strong>\u00a0)<\/strong>\u00a0e outro para\u00a0<strong>volume constante (c\u00a0<\/strong><strong><sub>v<\/sub><\/strong><strong>\u00a0)<\/strong>\u00a0.\u00a0Observe que essa raz\u00e3o\u00a0<strong>\u03ba\u00a0\u00a0<\/strong><strong>= c\u00a0<\/strong><strong><sub>p<\/sub><\/strong><strong>\u00a0\/ c\u00a0<\/strong><strong><sub>v<\/sub><\/strong>\u00a0\u00e9 um fator na determina\u00e7\u00e3o da velocidade do som em um g\u00e1s e em outros processos adiab\u00e1ticos.<\/span><\/p>\n<p><strong><span>Outra rela\u00e7\u00e3o p, V, T<\/span><\/strong><\/p>\n<p><a href=\"https:\/\/thermal-engineering.org\/wp-content\/uploads\/2019\/05\/pVT-relation-isentropic-process.png\"><img loading=\"lazy\" class=\"aligncenter size-full wp-image-17281 lazy-loaded\" src=\"https:\/\/thermal-engineering.org\/wp-content\/uploads\/2019\/05\/pVT-relation-isentropic-process.png\" alt=\"rela\u00e7\u00e3o p, V, T - processo isentr\u00f3pico\" width=\"209\" height=\"72\" data-lazy-type=\"image\" data-src=\"https:\/\/thermal-engineering.org\/wp-content\/uploads\/2019\/05\/pVT-relation-isentropic-process.png\" \/><\/a><\/p>\n<p><span>Em um\u00a0<\/span><strong><span>diagrama de pV<\/span><\/strong><span>\u00a0, o processo ocorre ao longo de uma linha (chamada\u00a0<\/span><strong><span>adiabat<\/span><\/strong><span>\u00a0) que possui a equa\u00e7\u00e3o\u00a0<\/span><strong><span>p = constante \/ V\u00a0<\/span><sup><span>\u03ba<\/span><\/sup><\/strong><span>\u00a0.\u00a0<\/span><strong><span>Para um g\u00e1s ideal e um processo politr\u00f3pico, o caso\u00a0<\/span><i><span>n = \u03ba\u00a0<\/span><\/i><\/strong><span><strong>corresponde a um processo isentr\u00f3pico.<\/strong><\/span><i>\u00a0\u00a0<\/i><\/p>\n<\/div>\n<\/div>\n<div class=\"lgc-column lgc-grid-parent lgc-grid-100 lgc-tablet-grid-100 lgc-mobile-grid-100 lgc-equal-heights  lgc-first lgc-last\">\n<div class=\"inside-grid-column\">\n<div class=\"su-spacer\"><\/div>\n<h2><span>Exemplo: Expans\u00e3o Isentr\u00f3pica na Turbina a G\u00e1s<\/span><\/h2>\n<figure id=\"attachment_17284\" class=\"wp-caption alignright\" aria-describedby=\"caption-attachment-17284\"><a href=\"https:\/\/thermal-engineering.org\/wp-content\/uploads\/2019\/05\/P-V-diagram-isentropic-process.png\"><img loading=\"lazy\" class=\"size-medium wp-image-17284 lazy-loaded\" src=\"https:\/\/thermal-engineering.org\/wp-content\/uploads\/2019\/05\/P-V-diagram-isentropic-process-300x251.png\" alt=\"Diagrama PV - processo isentr\u00f3pico\" width=\"300\" height=\"251\" data-lazy-type=\"image\" data-src=\"https:\/\/thermal-engineering.org\/wp-content\/uploads\/2019\/05\/P-V-diagram-isentropic-process-300x251.png\" \/><\/a><figcaption id=\"caption-attachment-17284\" class=\"wp-caption-text\"><span>Diagrama PV de uma expans\u00e3o isentr\u00f3pica de h\u00e9lio (3 \u2192 4) em uma turbina a g\u00e1s.<\/span><\/figcaption><\/figure>\n<p><span>Assuma uma\u00a0<\/span><strong><span>expans\u00e3o isentr\u00f3pica<\/span><\/strong><span>\u00a0de h\u00e9lio (\u00a0<\/span><strong><span>3 \u2192 4<\/span><\/strong><span>\u00a0) em uma\u00a0<\/span><strong><span>turbina a g\u00e1s<\/span><\/strong><span>\u00a0.\u00a0Como o h\u00e9lio se comporta quase como um\u00a0<\/span><a title=\"O que \u00e9 o g\u00e1s ideal\" href=\"https:\/\/www.nuclear-power.com\/nuclear-engineering\/thermodynamics\/ideal-gas-law\/what-is-ideal-gas\/\"><span>g\u00e1s ideal<\/span><\/a><span>\u00a0, use a\u00a0<\/span><a title=\"Lei do g\u00e1s ideal\" href=\"https:\/\/www.nuclear-power.com\/nuclear-engineering\/thermodynamics\/ideal-gas-law\/\"><span>lei do g\u00e1s ideal<\/span><\/a><span>\u00a0para calcular a\u00a0<\/span><strong><span>temperatura<\/span><\/strong><span>\u00a0de\u00a0<strong>sa\u00edda<\/strong>\u00a0do g\u00e1s (\u00a0<\/span><strong><span>T\u00a0<\/span><sub><span>4, \u00e9<\/span><\/sub><\/strong><span>\u00a0).\u00a0Nessas turbinas, o est\u00e1gio de alta press\u00e3o recebe g\u00e1s (ponto 3 na figura; p\u00a0<\/span><sub><span>3<\/span><\/sub><span>\u00a0=\u00a0<\/span><strong><span>6,7 MPa<\/span><\/strong><span>\u00a0;\u00a0<\/span><strong><span>T\u00a0<\/span><sub><span>3<\/span><\/sub><span>\u00a0= 1190 K<\/span><\/strong><span>\u00a0(917 \u00b0 C)) de um trocador de calor e o esgota em outro trocador de calor, onde a press\u00e3o de sa\u00edda \u00e9 p\u00a0<\/span><sub><span>4<\/span><\/sub><span>\u00a0=\u00a0<\/span><strong><span>2,78 MPa<\/span><\/strong><span>\u00a0(ponto 4)\u00a0<\/span><strong><span>.<\/span><\/strong><\/p>\n<p><strong><span>Solu\u00e7\u00e3o:<\/span><\/strong><\/p>\n<p><span>A temperatura de sa\u00edda do g\u00e1s, T\u00a0<\/span><sub><span>4, \u00e9<\/span><\/sub><span>\u00a0, pode ser calculada usando a rela\u00e7\u00e3o\u00a0<\/span><strong><span>p, V, T<\/span><\/strong><span>\u00a0para o processo isentr\u00f3pico (processo adiab\u00e1tico revers\u00edvel):<\/span><\/p>\n<p><a href=\"https:\/\/thermal-engineering.org\/wp-content\/uploads\/2019\/05\/pVT-relation-isentropic-process.png\"><img loading=\"lazy\" class=\"aligncenter size-full wp-image-17281 lazy-loaded\" src=\"https:\/\/thermal-engineering.org\/wp-content\/uploads\/2019\/05\/pVT-relation-isentropic-process.png\" alt=\"rela\u00e7\u00e3o p, V, T - processo isentr\u00f3pico\" width=\"209\" height=\"72\" data-lazy-type=\"image\" data-src=\"https:\/\/thermal-engineering.org\/wp-content\/uploads\/2019\/05\/pVT-relation-isentropic-process.png\" \/><\/a><\/p>\n<p><span>Nesta equa\u00e7\u00e3o, o fator para o h\u00e9lio \u00e9 igual a\u00a0<\/span><strong><span>\u03ba\u00a0<\/span><\/strong><strong><span>= c\u00a0<\/span><sub><span>p<\/span><\/sub><span>\u00a0\/ c\u00a0<\/span><sub><span>v<\/span><\/sub><span>\u00a0= 1,66<\/span><\/strong><span>\u00a0.\u00a0A partir da equa\u00e7\u00e3o anterior, segue que a temperatura de sa\u00edda do g\u00e1s,\u00a0<\/span><strong><span>T\u00a0<\/span><sub><span>4<\/span><\/sub><\/strong><span>\u00a0, \u00e9:<\/span><\/p>\n<p><a href=\"https:\/\/thermal-engineering.org\/wp-content\/uploads\/2019\/05\/isentropic-process-example.png\"><img loading=\"lazy\" class=\"aligncenter size-full wp-image-17283 lazy-loaded\" src=\"https:\/\/thermal-engineering.org\/wp-content\/uploads\/2019\/05\/isentropic-process-example.png\" alt=\"processo isentr\u00f3pico - exemplo\" width=\"503\" height=\"84\" data-lazy-type=\"image\" data-src=\"https:\/\/thermal-engineering.org\/wp-content\/uploads\/2019\/05\/isentropic-process-example.png\" \/><\/a><\/p>\n<\/div>\n<\/div>\n<div class=\"lgc-column lgc-grid-parent lgc-grid-100 lgc-tablet-grid-100 lgc-mobile-grid-100 lgc-equal-heights  lgc-first lgc-last\">\n<div class=\"inside-grid-column\">\n<div class=\"su-spacer\"><\/div>\n<h2><span>Exemplo: Expans\u00e3o Isentr\u00f3pica na Turbina a G\u00e1s<\/span><\/h2>\n<figure id=\"attachment_16843\" class=\"wp-caption alignright\" aria-describedby=\"caption-attachment-16843\"><a href=\"https:\/\/thermal-engineering.org\/wp-content\/uploads\/2019\/05\/first-law-example-brayton-cycle.png\"><img loading=\"lazy\" class=\"size-medium wp-image-16843 lazy-loaded\" src=\"https:\/\/thermal-engineering.org\/wp-content\/uploads\/2019\/05\/first-law-example-brayton-cycle-300x244.png\" alt=\"primeira lei - exemplo - ciclo de brayton\" width=\"300\" height=\"244\" data-lazy-type=\"image\" data-src=\"https:\/\/thermal-engineering.org\/wp-content\/uploads\/2019\/05\/first-law-example-brayton-cycle-300x244.png\" \/><\/a><figcaption id=\"caption-attachment-16843\" class=\"wp-caption-text\"><span>O ciclo ideal de Brayton consiste em quatro processos termodin\u00e2micos.\u00a0Dois processos isentr\u00f3picos e dois processos isob\u00e1ricos.<\/span><\/figcaption><\/figure>\n<p><span>Vamos assumir o\u00a0\u00a0<\/span><strong><span>ciclo de Brayton ideal<\/span><\/strong><span>\u00a0\u00a0que descreve o funcionamento de um\u00a0\u00a0<strong>motor de calor com\u00a0<\/strong><\/span><strong><span>press\u00e3o constante<\/span><\/strong>\u00a0<span>\u00a0.\u00a0<strong>Os modernos<\/strong>\u00a0\u00a0motores de\u00a0<strong>turbina a g\u00e1s<\/strong>\u00a0e os motores a\u00a0\u00a0<strong>jato de respira\u00e7\u00e3o<\/strong>\u00a0\u00a0tamb\u00e9m seguem o ciclo de Brayton.<\/span><\/p>\n<p><span>O ciclo ideal de Brayton consiste em quatro processos termodin\u00e2micos.\u00a0Dois processos isentr\u00f3picos e dois processos isob\u00e1ricos.<\/span><\/p>\n<ol>\n<li><strong><span>compress\u00e3o isentr\u00f3pica<\/span><\/strong><span>\u00a0\u00a0&#8211; o ar ambiente \u00e9 aspirado para o compressor, onde \u00e9 pressurizado (1 \u2192 2).\u00a0O trabalho necess\u00e1rio para o compressor \u00e9 dado por\u00a0\u00a0<\/span><strong><span>W\u00a0<\/span><sub><span>C<\/span><\/sub><span>\u00a0\u00a0= H\u00a0<\/span><sub><span>2<\/span><\/sub><span>\u00a0\u00a0&#8211; H\u00a0<\/span><sub><span>1<\/span><\/sub><span>\u00a0.<\/span><\/strong><\/li>\n<li><strong><span>adi\u00e7\u00e3o de calor isob\u00e1rico<\/span><\/strong><span>\u00a0\u00a0&#8211; o ar comprimido passa por uma c\u00e2mara de combust\u00e3o, onde o combust\u00edvel \u00e9 queimado e o ar ou outro meio \u00e9 aquecido (2 \u2192 3).\u00a0\u00c9 um processo de press\u00e3o constante, j\u00e1 que a c\u00e2mara est\u00e1 aberta para entrar e sair.\u00a0O calor l\u00edquido adicionado \u00e9 dado por\u00a0\u00a0<\/span><strong><span>Q\u00a0<\/span><sub><span>add<\/span><\/sub><span>\u00a0\u00a0= H\u00a0<\/span><sub><span>3\u00a0<\/span><\/sub><span>\u00a0&#8211; H\u00a0<\/span><sub><span>2<\/span><\/sub><\/strong><\/li>\n<li><strong><span>expans\u00e3o isentr\u00f3pica<\/span><\/strong><span>\u00a0\u00a0&#8211; o ar aquecido e pressurizado se expande na turbina, gasta sua energia.\u00a0O trabalho realizado pela turbina \u00e9 dado por\u00a0\u00a0<\/span><strong><span>W\u00a0<\/span><sub><span>T<\/span><\/sub><span>\u00a0\u00a0= H\u00a0<\/span><sub><span>4<\/span><\/sub><span>\u00a0\u00a0&#8211; H\u00a0<\/span><sub><span>3<\/span><\/sub><\/strong><\/li>\n<li><strong><span>rejei\u00e7\u00e3o de calor isob\u00e1rica<\/span><\/strong><span>\u00a0\u00a0&#8211; o calor residual deve ser rejeitado para fechar o ciclo.\u00a0O calor l\u00edquido rejeitado \u00e9 dado por\u00a0\u00a0<\/span><strong><span>Q\u00a0<\/span><sub><span>re<\/span><\/sub><span>\u00a0\u00a0= H\u00a0<\/span><sub><span>4\u00a0<\/span><\/sub><span>\u00a0&#8211; H\u00a0<\/span><sub><span>1<\/span><\/sub><\/strong><\/li>\n<\/ol>\n<p><span>Como pode ser visto, podemos descrever e calcular (por exemplo,\u00a0<\/span><a title=\"Efici\u00eancia t\u00e9rmica\" href=\"https:\/\/www.thermal-engineering.org\/pt-br\/o-que-e-eficiencia-termica-definicao\/\"><span>efici\u00eancia t\u00e9rmica<\/span><\/a><span>\u00a0) esses ciclos (da mesma forma para o\u00a0\u00a0<\/span><strong><span>ciclo de Rankine<\/span><\/strong><span>\u00a0) usando\u00a0\u00a0<\/span><a href=\"https:\/\/www.nuclear-power.com\/nuclear-engineering\/thermodynamics\/what-is-energy-physics\/what-is-enthalpy\/\"><span>entalpias<\/span><\/a><span>\u00a0.<\/span><\/p>\n<p><span>Veja tamb\u00e9m:\u00a0<\/span><a title=\"Efici\u00eancia t\u00e9rmica do ciclo de Brayton\" href=\"https:\/\/www.nuclear-power.com\/nuclear-engineering\/thermodynamics\/laws-of-thermodynamics\/thermal-efficiency\/thermal-efficiency-of-brayton-cycle\/\"><span>Efici\u00eancia t\u00e9rmica do ciclo de Brayton<\/span><\/a><\/p>\n<\/div>\n<\/div>\n<div class=\"lgc-column lgc-grid-parent lgc-grid-100 lgc-tablet-grid-100 lgc-mobile-grid-100 lgc-equal-heights  lgc-first lgc-last\">\n<div class=\"inside-grid-column\">\n<div class=\"su-spacer\"><\/div>\n<h2><span>Processos isentr\u00f3picos em ciclos termodin\u00e2micos<\/span><\/h2>\n<p><strong><span>Ciclo de Carnot ideal<\/span><\/strong><\/p>\n<ul>\n<li><span>Compress\u00e3o isentr\u00f3pica<\/span><\/li>\n<li><span>Expans\u00e3o isentr\u00f3pica<\/span><\/li>\n<\/ul>\n<p><strong><span>Ciclo Rankine Ideal<\/span><\/strong><\/p>\n<ul>\n<li><span>Compress\u00e3o isentr\u00f3pica em uma bomba<\/span><\/li>\n<li><span>Expans\u00e3o isentr\u00f3pica em uma turbina<\/span><\/li>\n<\/ul>\n<p><strong><span>Ciclo de Brayton ideal<\/span><\/strong><\/p>\n<ul>\n<li><span>Compress\u00e3o isentr\u00f3pica em um compressor<\/span><\/li>\n<li><span>Expans\u00e3o isentr\u00f3pica em uma turbina<\/span><\/li>\n<\/ul>\n<p><strong><span>Ciclo Otto Ideal<\/span><\/strong><\/p>\n<ul>\n<li><span>Compress\u00e3o isentr\u00f3pica<\/span><\/li>\n<li><span>Expans\u00e3o isentr\u00f3pica<\/span><\/li>\n<\/ul>\n<p><strong><span>Ciclo Diesel Ideal<\/span><\/strong><\/p>\n<ul>\n<li><span>Compress\u00e3o isentr\u00f3pica<\/span><\/li>\n<li><span>Expans\u00e3o isentr\u00f3pica<\/span><\/li>\n<\/ul>\n<\/div>\n<\/div>\n<div class=\"lgc-column lgc-grid-parent lgc-grid-60 lgc-tablet-grid-60 lgc-mobile-grid-100 lgc-equal-heights  lgc-first\">\n<div class=\"inside-grid-column\">\n<div class=\"su-spacer\"><\/div>\n<h2><span>Efici\u00eancia isentr\u00f3pica &#8211; turbina, compressor, bocal<\/span><\/h2>\n<p><span>Nos cap\u00edtulos anteriores assumiu-se que a expans\u00e3o do g\u00e1s \u00e9\u00a0<\/span><strong><span>isentr\u00f3pica<\/span><\/strong><span>\u00a0e, portanto, utilizou-se\u00a0<\/span><strong><span>o t\u00a0<\/span><sub><span>4, \u00e9<\/span><\/sub><\/strong><span>\u00a0\u00a0como a temperatura de sa\u00edda do g\u00e1s.\u00a0Essas premissas s\u00e3o aplic\u00e1veis \u200b\u200bapenas aos ciclos ideais.<\/span><\/p>\n<p><span>A maioria\u00a0<\/span><strong><span>dos dispositivos de fluxo constante<\/span><\/strong><span>\u00a0(turbinas, compressores, bicos) opera em\u00a0<\/span><strong><span>condi\u00e7\u00f5es adiab\u00e1ticas<\/span><\/strong><span>\u00a0, mas n\u00e3o s\u00e3o verdadeiramente isentr\u00f3picos, mas s\u00e3o idealizados como isentr\u00f3picos para fins de c\u00e1lculo.\u00a0Definimos os par\u00e2metros\u00a0<\/span><strong><em><span>\u03b7\u00a0<\/span><\/em><\/strong><strong><em><sub><span>T<\/span><\/sub><\/em><\/strong><strong><em><span>\u00a0,\u00a0<\/span><\/em><\/strong>\u00a0<strong><em><span>\u03b7\u00a0<\/span><\/em><\/strong><strong><em><sub><span>C<\/span><\/sub><\/em><\/strong><strong><em><span>\u00a0, \u03b7\u00a0<\/span><\/em><\/strong><strong><em><sub><span>N<\/span><\/sub><\/em><\/strong><strong><em><span>\u00a0,<\/span><\/em><\/strong><span>\u00a0como uma\u00a0<\/span><strong><span>raz\u00e3o<\/span><\/strong><span>\u00a0entre\u00a0<\/span><strong><span>o trabalho real realizado<\/span><\/strong><span>\u00a0por dispositivo e o\u00a0<\/span><strong><span>trabalho por dispositivo quando operado em condi\u00e7\u00f5es isentr\u00f3picas<\/span><\/strong><span>\u00a0(no caso de turbinas).\u00a0Essa rela\u00e7\u00e3o \u00e9 conhecida como\u00a0<\/span><strong><span>efici\u00eancia isentr\u00f3pica de turbina \/ compressor \/ bico<\/span><\/strong><span>\u00a0.<\/span><\/p>\n<p><span>Esses par\u00e2metros descrevem com que efici\u00eancia uma turbina, compressor ou bico se aproxima de um dispositivo isentr\u00f3pico correspondente.\u00a0Este par\u00e2metro reduz a efici\u00eancia geral e a produ\u00e7\u00e3o do trabalho.\u00a0Para turbinas, o valor de\u00a0<\/span><strong><em><span>\u03b7\u00a0<\/span><\/em><\/strong><strong><em><sub><span>T<\/span><\/sub><\/em><\/strong><span>\u00a0\u00e9 tipicamente de 0,7 a 0,9 (70-90%).<\/span><\/p>\n<p><a href=\"https:\/\/thermal-engineering.org\/wp-content\/uploads\/2019\/05\/Isentropic-Efficiency-equations.png\"><img loading=\"lazy\" class=\"aligncenter size-full wp-image-17298 lazy-loaded\" src=\"https:\/\/thermal-engineering.org\/wp-content\/uploads\/2019\/05\/Isentropic-Efficiency-equations.png\" alt=\"Efici\u00eancia isentr\u00f3pica - equa\u00e7\u00f5es\" width=\"532\" height=\"357\" data-lazy-type=\"image\" data-src=\"https:\/\/thermal-engineering.org\/wp-content\/uploads\/2019\/05\/Isentropic-Efficiency-equations.png\" \/><\/a><\/p>\n<\/div>\n<\/div>\n<div class=\"lgc-column lgc-grid-parent lgc-grid-40 lgc-tablet-grid-40 lgc-mobile-grid-100 lgc-equal-heights  lgc-last\">\n<div class=\"inside-grid-column\"><a href=\"https:\/\/thermal-engineering.org\/wp-content\/uploads\/2019\/05\/Isentropic-vs.-adiabatic-compression.png\"><img loading=\"lazy\" class=\"aligncenter size-medium wp-image-17268 lazy-loaded\" src=\"https:\/\/thermal-engineering.org\/wp-content\/uploads\/2019\/05\/Isentropic-vs.-adiabatic-compression-274x300.png\" alt=\"Compress\u00e3o isentr\u00f3pica vs. adiab\u00e1tica\" width=\"274\" height=\"300\" data-lazy-type=\"image\" data-src=\"https:\/\/thermal-engineering.org\/wp-content\/uploads\/2019\/05\/Isentropic-vs.-adiabatic-compression-274x300.png\" \/><\/a><\/p>\n<figure id=\"attachment_17267\" class=\"wp-caption aligncenter\" aria-describedby=\"caption-attachment-17267\"><a href=\"https:\/\/thermal-engineering.org\/wp-content\/uploads\/2019\/05\/Isentropic-vs.-adiabatic-expansion.png\"><img loading=\"lazy\" class=\"size-medium wp-image-17267 lazy-loaded\" src=\"https:\/\/thermal-engineering.org\/wp-content\/uploads\/2019\/05\/Isentropic-vs.-adiabatic-expansion-276x300.png\" alt=\"Expans\u00e3o isentr\u00f3pica vs. adiab\u00e1tica\" width=\"276\" height=\"300\" data-lazy-type=\"image\" data-src=\"https:\/\/thermal-engineering.org\/wp-content\/uploads\/2019\/05\/Isentropic-vs.-adiabatic-expansion-276x300.png\" \/><\/a><figcaption id=\"caption-attachment-17267\" class=\"wp-caption-text\"><span>O processo isentr\u00f3pico \u00e9 um caso especial de processos adiab\u00e1ticos.\u00a0\u00c9 um processo adiab\u00e1tico revers\u00edvel.\u00a0Um processo isentr\u00f3pico tamb\u00e9m pode ser chamado de processo de entropia constante.<\/span><\/figcaption><\/figure>\n<\/div>\n<\/div>\n<div class=\"lgc-column lgc-grid-parent lgc-grid-100 lgc-tablet-grid-100 lgc-mobile-grid-100 lgc-equal-heights  lgc-first lgc-last\">\n<div class=\"inside-grid-column\">\n<div class=\"su-spacer\"><\/div>\n<h2><span>Exemplo: Efici\u00eancia isentr\u00f3pica da turbina<\/span><\/h2>\n<figure id=\"attachment_17267\" class=\"wp-caption alignright\" aria-describedby=\"caption-attachment-17267\"><a href=\"https:\/\/thermal-engineering.org\/wp-content\/uploads\/2019\/05\/Isentropic-vs.-adiabatic-expansion.png\"><img loading=\"lazy\" class=\"size-medium wp-image-17267 lazy-loaded\" src=\"https:\/\/thermal-engineering.org\/wp-content\/uploads\/2019\/05\/Isentropic-vs.-adiabatic-expansion-276x300.png\" alt=\"Expans\u00e3o isentr\u00f3pica vs. adiab\u00e1tica\" width=\"276\" height=\"300\" data-lazy-type=\"image\" data-src=\"https:\/\/thermal-engineering.org\/wp-content\/uploads\/2019\/05\/Isentropic-vs.-adiabatic-expansion-276x300.png\" \/><\/a><figcaption id=\"caption-attachment-17267\" class=\"wp-caption-text\"><span>O processo isentr\u00f3pico \u00e9 um caso especial de processos adiab\u00e1ticos.\u00a0\u00c9 um processo adiab\u00e1tico revers\u00edvel.\u00a0Um processo isentr\u00f3pico tamb\u00e9m pode ser chamado de processo de entropia constante.<\/span><\/figcaption><\/figure>\n<p><span>Assuma uma\u00a0<\/span><strong><span>expans\u00e3o isentr\u00f3pica<\/span><\/strong><span>\u00a0de h\u00e9lio (3 \u2192 4) em uma turbina a g\u00e1s.\u00a0Nessas turbinas, o est\u00e1gio de alta press\u00e3o recebe g\u00e1s (ponto 3 na figura; p\u00a0<\/span><sub><span>3<\/span><\/sub><span>\u00a0=\u00a0<\/span><strong><span>6,7 MPa<\/span><\/strong><span>\u00a0; T\u00a0<\/span><sub><span>3<\/span><\/sub><span>\u00a0= 1190 K (917 \u00b0 C)) de um trocador de calor e o esgota em outro trocador de calor, onde a press\u00e3o de sa\u00edda \u00e9 p\u00a0<\/span><sub><span>4<\/span><\/sub><span>\u00a0=\u00a0<\/span><strong><span>2,78 MPa<\/span><\/strong><span>\u00a0(ponto 4)\u00a0<\/span><strong><span>.\u00a0<\/span><\/strong><span>A temperatura (para o processo isentr\u00f3pico) do g\u00e1s na sa\u00edda da turbina \u00e9 T\u00a0<\/span><sub><span>4s<\/span><\/sub><span>\u00a0= 839 K (566 \u00b0 C).<\/span><\/p>\n<p><strong><span>Calcule<\/span><\/strong><span>\u00a0o trabalho realizado por esta turbina e calcule a temperatura real na sa\u00edda da turbina, quando a\u00a0<\/span><strong><span>efici\u00eancia isentr\u00f3pica da turbina<\/span><\/strong><span>\u00a0for\u00a0<\/span><strong><span>\u03b7\u00a0<\/span><\/strong><strong><sub><span>T<\/span><\/sub><\/strong><strong><span>\u00a0= 0,91 (91%)<\/span><\/strong><span>\u00a0.<\/span><\/p>\n<p><strong><span>Solu\u00e7\u00e3o:<\/span><\/strong><\/p>\n<p><span>A partir da primeira lei da termodin\u00e2mica, o trabalho realizado pela turbina em um processo isentr\u00f3pico pode ser calculado a partir de:<\/span><\/p>\n<p><strong><span>W\u00a0<\/span><\/strong><strong><sub><span>T<\/span><\/sub><\/strong><strong><span>\u00a0= h\u00a0<\/span><\/strong><strong><sub><span>3<\/span><\/sub><\/strong><strong><span>\u00a0&#8211; h\u00a0<\/span><\/strong><strong><sub><span>4s<\/span><\/sub><\/strong><strong><span>\u00a0\u00a0\u00a0\u00a0\u00a0\u2192 W\u00a0<\/span><\/strong><strong><sub><span>Ts<\/span><\/sub><\/strong><strong><span>\u00a0=\u00a0<\/span><em><span>c\u00a0<\/span><\/em><\/strong><strong><em><sub><span>p<\/span><\/sub><\/em><\/strong><strong><em><span>\u00a0(T\u00a0<\/span><\/em><\/strong><strong><em><sub><span>3<\/span><\/sub><\/em><\/strong><strong><em><span>\u00a0&#8211; T\u00a0<\/span><\/em><\/strong><strong><em><sub><span>4s<\/span><\/sub><\/em><\/strong><strong><em><span>\u00a0)<\/span><\/em><\/strong><\/p>\n<p><span>Pela Lei do G\u00e1s Ideal, sabemos que o calor molar espec\u00edfico de um g\u00e1s ideal monat\u00f4mico \u00e9:<\/span><\/p>\n<p><strong><em><span>C\u00a0<\/span><\/em><\/strong><strong><em><sub><span>v<\/span><\/sub><\/em><\/strong><strong><em><span>\u00a0= 3 \/ 2R = 12,5 J \/ mol K<\/span><\/em><\/strong><span>\u00a0e<\/span><strong><em><span>\u00a0C\u00a0<\/span><\/em><\/strong><strong><em><sub><span>p<\/span><\/sub><\/em><\/strong><strong><em><span>\u00a0= C\u00a0<\/span><\/em><\/strong><strong><em><sub><span>v<\/span><\/sub><\/em><\/strong><strong><em><span>\u00a0+ R = 5 \/ 2R = 20,8 J \/ mol K<\/span><\/em><\/strong><\/p>\n<p><span>Transferimos as capacidades de calor espec\u00edficas em unidades de\u00a0<\/span><strong><span>J \/ kg K via:<\/span><\/strong><\/p>\n<p><strong><em><span>c\u00a0<\/span><\/em><\/strong><strong><em><sub><span>p<\/span><\/sub><\/em><\/strong><strong><em><span>\u00a0= C\u00a0<\/span><\/em><\/strong><strong><em><sub><span>p<\/span><\/sub><\/em><\/strong><strong><em><span>\u00a0.\u00a01 \/ M (peso molar de h\u00e9lio) = 20,8 x 4,10\u00a0<\/span><\/em><\/strong><strong><em><sup><span>-3<\/span><\/sup><\/em><\/strong><strong><em><span>\u00a0= 5200 J \/ kg K<\/span><\/em><\/strong><\/p>\n<p><span>O trabalho realizado pela turbina a g\u00e1s no processo isentr\u00f3pico \u00e9 ent\u00e3o:<\/span><\/p>\n<p><strong><em><span>W\u00a0<\/span><\/em><\/strong><strong><em><sub><span>T, s<\/span><\/sub><\/em><\/strong><strong><em><span>\u00a0= c\u00a0<\/span><\/em><\/strong><strong><em><sub><span>p<\/span><\/sub><\/em><\/strong><strong><em><span>\u00a0(\u00a0<\/span><\/em><\/strong><strong><em><sub><span>T3<\/span><\/sub><\/em><\/strong><strong><em><span>\u00a0&#8211;\u00a0<\/span><\/em><\/strong><strong><em><sub><span>T4s<\/span><\/sub><\/em><\/strong><strong><em><span>\u00a0) = 5200 x (1190 &#8211; 839) = 1,825 MJ \/ kg<\/span><\/em><\/strong><\/p>\n<p><span>O trabalho real realizado pela turbina a g\u00e1s no processo adiab\u00e1tico \u00e9 ent\u00e3o:<\/span><br \/>\n<strong><em><span>WT\u00a0<\/span><\/em><\/strong><strong><em><sub><span>, real<\/span><\/sub><\/em><\/strong><strong><em><span>\u00a0=\u00a0<\/span><\/em><\/strong><strong><em><sub><span>cp<\/span><\/sub><\/em><\/strong><strong><em><span>\u00a0(\u00a0<\/span><\/em><\/strong><strong><em><sub><span>T3<\/span><\/sub><\/em><\/strong><strong><em><span>\u00a0&#8211;\u00a0<\/span><\/em><\/strong><strong><em><sub><span>T4s<\/span><\/sub><\/em><\/strong><strong><em><span>\u00a0).\u00a0<\/span><\/em><\/strong><strong><em><span>\u03b7\u00a0<\/span><\/em><\/strong><strong><em><sub><span>T<\/span><\/sub><\/em><\/strong>\u00a0<strong><em><span>= 5200 x (1190 &#8211; 839) x 0,91 = 1,661 MJ \/ kg<\/span><\/em><\/strong><\/p>\n<\/div>\n<\/div>\n<\/div>\n<div><\/div>\n<div><\/div>\n<div>\n<p>&#8230;&#8230;&#8230;&#8230;&#8230;&#8230;&#8230;&#8230;&#8230;&#8230;&#8230;&#8230;&#8230;&#8230;&#8230;&#8230;&#8230;&#8230;&#8230;&#8230;&#8230;&#8230;&#8230;&#8230;&#8230;&#8230;&#8230;&#8230;&#8230;&#8230;&#8230;&#8230;&#8230;&#8230;&#8230;&#8230;&#8230;&#8230;&#8230;&#8230;&#8230;&#8230;&#8230;&#8230;&#8230;&#8230;&#8230;&#8230;.<\/p>\n<p>Este artigo \u00e9 baseado na tradu\u00e7\u00e3o autom\u00e1tica do artigo original em ingl\u00eas. Para mais informa\u00e7\u00f5es, consulte o artigo em ingl\u00eas. Voc\u00ea pode nos ajudar. Se voc\u00ea deseja corrigir a tradu\u00e7\u00e3o, envie-a para: translations@nuclear-power.com ou preencha o formul\u00e1rio de tradu\u00e7\u00e3o on-line. Agradecemos sua ajuda, atualizaremos a tradu\u00e7\u00e3o o mais r\u00e1pido poss\u00edvel. Obrigado.<\/p>\n<\/div>\n","protected":false},"excerpt":{"rendered":"<p>Um processo isentr\u00f3pico \u00e9 um processo termodin\u00e2mico, no qual a entropia do fluido ou g\u00e1s permanece constante. \u00c9 tamb\u00e9m chamado de processo de entropia constante. Engenharia T\u00e9rmica Processo isentr\u00f3pico Um\u00a0processo isentr\u00f3pico\u00a0\u00e9 um\u00a0processo termodin\u00e2mico\u00a0, no qual a\u00a0entropia\u00a0do fluido ou g\u00e1s permanece constante.\u00a0Isso significa que o\u00a0processo isentr\u00f3pico\u00a0\u00e9 um caso especial de um\u00a0processo adiab\u00e1tico\u00a0no qual n\u00e3o h\u00e1 transfer\u00eancia &#8230; <a title=\"O que \u00e9 processo isentr\u00f3pico &#8211; defini\u00e7\u00e3o\" class=\"read-more\" href=\"https:\/\/www.thermal-engineering.org\/pt-br\/o-que-e-processo-isentropico-definicao\/\" aria-label=\"More on O que \u00e9 processo isentr\u00f3pico &#8211; defini\u00e7\u00e3o\">Ler mais<\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":[],"categories":[14],"tags":[],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v15.4 - https:\/\/yoast.com\/wordpress\/plugins\/seo\/ -->\n<title>O que \u00e9 processo isentr\u00f3pico - defini\u00e7\u00e3o<\/title>\n<meta name=\"description\" content=\"Um processo isentr\u00f3pico \u00e9 um processo termodin\u00e2mico, no qual a entropia do fluido ou g\u00e1s permanece constante. \u00c9 tamb\u00e9m chamado de processo de entropia constante. 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